chore: fix StopIteration on bgp test (#20746)

Description of PR
Summary: Fix stop iteration for bgp t0/t1 device

    @decorator.decorator
    def _fixture_generator_decorator(fixture_generator, *args, **kargs):
        # setup, to the first yield in fixture
        logging.info("-" * 20 + (" fixture %s setup starts " % fixture_generator.__name__) + "-" * 20)
        it = fixture_generator(*args, **kargs)
        try:
>           res = next(it)
E           StopIteration
Fixes # (issue) 3498901

Signed-off-by: Austin Pham <[email protected]>

Author: auspham

tests/snappi_tests/bgp/conftest.py

@@ -280,6 +280,7 @@ def _handler(key, arr_dict_value):
 @pytest.fixture(scope="session", autouse=True)
 def initial_setup(duthosts, creds, tbinfo):
     if 'route_conv' not in tbinfo['topo']['name']:
+        yield
         return
 
     """Perform initial DUT configurations (T1, Fanout) for convergence tests (runs once per test session)."""